Ships Begin Search In Atlantic For Main Engine Of Delta Rocket

May 7, 1986|By John J. Glisch of The Sentinel Staff

CAPE CANAVERAL — Salvage ships searching for space shuttle wreckage began scouring the Atlantic Ocean on Tuesday for the main engine of a Delta rocket that failed after an electrical short apparently caused it to prematurely shut down.

Investigators hope electronic control boxes in the Delta's engine compartment will help pinpoint what caused the short, which probably made the engine stop 71 seconds after launch Saturday. The engine was supposed to stop at 3 minutes and 44 seconds.

''Having the physical evidence of what caused the premature shutdown would be helpful in ensuring ourselves that the inferences we are able to draw from telemetry and other data are correct,'' said Lawrence Ross, director of an eight-member NASA and Air Force team investigating the accident.

Other officials said tests to simulate the power fluctuations may turn up evidence of what caused the short by early next week.

The 116-foot Delta was carrying a $57.5 million GOES-7 weather satellite when two power surges and drops shot through the electrical system of the first-stage engine, Ross said Monday.

The fluctuations in power would have been enough to drain the main engine's battery and close the fuel valves.

The Delta started spinning out of control as soon as the engine stopped. A range safety officer sent a signal 20 seconds later to destroy the $30 million, three-stage rocket 15 miles above the Atlantic.

Radar trackings indicate the rocket's main engine compartment fell into 600 feet of water about 30 miles east of Cocoa Beach. Avionics equipment in the Delta's midsection also fell in the same area, said Air Force Col. Edward O'Connor, who leads the recovery operation for Challenger wreckage.

''I'm confident we'll find it,'' O'Connor said.

The electronic and avionics devices ''should be in good shape,'' he said, based on the condition of similar components recovered from Challenger since the shuttle accident Jan. 28.

Meanwhile, investigators at Vandenberg Air Force Base in California are close to determining the cause of an explosion there that destroyed a Titan 34D eight seconds after liftoff April 18.

The trade journal Aviation Week and Space Technology reported Monday that the Titan explosion occurred when the metal casing of one of two solid- fuel booster rockets ruptured.

A possible debonding of insulation inside the booster casing is suspected of causing the rupture, said the magazine.

The Titan's booster rockets are made by United Technologies. The twin solid-fuel boosters used on shuttles are made by Morton Thiokol.